JP2000215528A - Manufacture of optical information recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the generation of appearance defects and to improve the yield of an optical information recording medium by preventing a dyestuff solution from splashing. SOLUTION: In a method for manufacturing a heat mode type optical information recording medium, having a dyestuff recording layer capable of recording information on a base 202 by radiating a laser beam, when a dyestuff solution for forming the dyestuff recording layer is applied on the base 202 while rotating the base 202, the time from the time when application of the dyestuff solution is started until the time point when a valve is fully opened is set to so as to be 0.1 sec or longer. In order to satisfy this condition, the opening speed of the valve in a valve device 408 to 5% or larger to 50% or smaller with respect to the maximum speed, by setting the opening degree of a first speed controller 462 to 5% or larger to 50% or smaller.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a heat mode optical information recording medium capable of recording and reproducing information by using a laser beam.

[0002]

2. Description of the Related Art In general, as an optical information recording medium (optical disk) on which information can be recorded only once by a laser beam, there are a write-once CD (so-called CD-R) and a DVD-R. Compared to the production of (compact discs), it has the advantage that a small amount of CDs can be supplied to the market at a reasonable price and quickly, and the demand has increased with the recent spread of personal computers and the like.

A typical structure of a CD-R type optical information recording medium is a recording layer made of an organic dye, a light reflecting layer made of a metal such as gold on a transparent disc-shaped substrate having a thickness of about 1.2 mm,
Further, a protective layer made of resin is laminated in this order (see, for example, JP-A-6-150371).

A DVD-R type optical information recording medium is
It has a structure in which two disc-shaped substrates (having a thickness of about 0.6 mm) are bonded together with their respective information recording surfaces facing inward, and has a feature that the amount of recorded information is large.

For writing (recording) information on these optical information recording media, a laser beam in the near-infrared region (a laser beam having a wavelength of about 780 nm for CD-R and a wavelength of about 635 nm for DVD-R) is irradiated. The irradiation portion of the dye recording layer absorbs the light and locally raises the temperature, causing a physical or chemical change (for example, formation of pits) and changing its optical characteristics. Information is recorded.

On the other hand, information reading (reproduction) is usually
Reflection is performed by irradiating a laser beam having the same wavelength as the recording laser beam, so that the optical characteristics of the dye recording layer are changed between a portion (recorded portion due to pit generation) and a portion not changed (unrecorded portion). The information is reproduced by detecting the difference in rate.

[0007]

In some cases, a lot number indicating a manufacturing history of an optical disc, a manufacturer, a disc type display, and the like are printed on the inner peripheral transparent portion on the substrate. These printing forms have no effect on the recording on the optical disc itself, but emphasis is placed on appearance quality.

In the optical information recording medium as described above,
As shown in FIG. 14, when a recording layer made of an organic dye is formed on a substrate 500, a dye solution 502 is applied onto the substrate 500 through a nozzle 504 while rotating the substrate 500. The dye solution 502 that has fallen may be scattered in all directions, which may cause poor appearance of the transparent portion 506 on the inner peripheral side.

Therefore, as shown by a two-dot chain line in FIG.
A method of installing the mask 508 in a part where the droplets of the dye solution 502 are not desired to be attached can be considered. This may cause a new problem of causing a defect.

The present invention has been made in view of such problems, and prevents the occurrence of poor appearance by preventing the scattering of a dye solution, thereby improving the yield of an optical information recording medium. An object of the present invention is to provide a method for manufacturing an optical information recording medium.

[0011]

According to the present invention, there is provided a method of manufacturing a heat mode type optical information recording medium having a recording layer on which information can be recorded by irradiating a laser beam. When the solution for forming the recording layer is applied onto the substrate while allowing the solution to be applied, the time from the start of application of the solution until the application speed of the solution becomes constant is 0.1 second or more and 1 second or less. Is preferred.
Here, the time point when the application of the solution is started refers to the time point at which the solution starts to come out from the tip of the nozzle.

Normally, the discharge amount of the solution changes transiently with the passage of time from the start of the application of the solution, and finally reaches a constant discharge amount (stabilizes). That is, the above-mentioned “time from the start of applying the solution to the time when the application speed of the solution becomes constant” refers to the time from the start of applying the solution to the time when the discharge amount of the solution is settled (stabilized).

By setting this time to be at least 0.1 second and at most 1 second, it is possible to prevent the solution from scattering on all sides when the solution falls onto the substrate, thereby preventing appearance defects from occurring. can do. This leads to an improvement in the yield of the optical information recording medium.

In the above manufacturing method, in the case where a valve device for executing and stopping the discharge of the solution to the substrate by opening and closing a valve is used, the opening speed of the valve is set to 5% or more of the maximum speed. % Can be achieved. That is, the opening speed of the valve in the valve device for discharging the solution may be reduced.

In the case where a speed controller for controlling the flow rate of the fluid supplied to the valve device is used to open and close the valve with a fluid pressure, the speed controller for determining the flow rate of the fluid is used. May be set to 5% or more and 50% or less.

The solution may be a dye-containing organic solvent. Further, it is appropriate that the position where the coating is started is on the substrate, and the position where the coating is started is at least 5 mm away from the non-coated portion on the inner peripheral side on the substrate, that is, in the area to be formed as the recording layer. It is preferable that it is a portion closer to the outer peripheral side by 5 mm or more from the peripheral end.

If the position where the coating is started is sufficiently far from the non-coated portion on the inner peripheral side on the substrate, there is no problem even if the solution is scattered. This is because the scattered droplets flow away in the subsequent coating process.

Immediately after the start of coating, the discharge amount of the solution changes transiently with the lapse of time and is not stable.
It is preferable to start coating at a position slightly away from the innermost circumference. If the coating is started from the innermost circumference, it may cause unevenness of coating, and the inner circumferential edge of the recording layer may not be formed into a clean circle.

After the application is started, when the nozzle is moved at least once to the inner peripheral side, the inner peripheral edge of the recording layer becomes a clean circle.

However, if the coating is started outside the substrate, the solution scatters in various directions when it hits the outer peripheral edge of the substrate, and stains the vicinity of the coated portion, or the solution is applied to the back surface of the substrate. This causes a problem such as adhesion.

Therefore, the starting position of the coating is preferably on the substrate, more preferably 5 mm or more from the outer edge of the substrate. In addition, 5 mm or more, preferably 10 mm or more from an uncoated portion on the inner peripheral side on the substrate,
More preferably, it is 15 mm or more toward the outer periphery.

The pressure applied to the solution is 1 kgf / cm ²
The following is preferred. Generally, when applying a solution to a substrate,
When the discharge of the solution is suddenly started, scattering of the solution in all directions occurs, but when the pressure applied to the solution is small,
Since it does not scatter greatly, there is no problem such as poor appearance.

However, if the pressure is too low, the discharge rate per unit time is reduced and the coating speed is reduced, so that it takes time to apply a prescribed amount of the solution, resulting in a decrease in throughput. Production efficiency may be reduced.

Therefore, the preferable range of the pressure applied to the solution is, as described above, an upper limit of 1 kgf / cm ^2.
Or less, preferably 0.8 kgf / cm ² or less, most preferably 0.6 kgf / cm ² or less. The lower limit is 0.02 kgf / cm ² or more, preferably 0.05
kgf / cm ² or more, most preferably 0.1 kgf / c
m ² or more.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment in which a method for manufacturing an optical information recording medium according to the present invention is applied to a system for manufacturing an optical disk such as a CD-R (hereinafter simply referred to as a manufacturing system according to the embodiment). Will be described with reference to FIGS.

The manufacturing system 10 according to the present embodiment
As shown in FIG. 1, for example, two molding equipments (first and second molding apparatuses) for producing a substrate by injection molding, compression molding or injection compression molding.
And a second molding facility 12A and 12B), a coating facility 14 for forming a dye recording layer on the substrate by applying and drying a dye solution on one principal surface of the substrate, and a dye recording layer on the substrate. After forming a light reflection layer on the light reflection layer by, for example, sputtering, and then applying a UV curing liquid on the light reflection layer,
And a post-processing facility 16 for forming a protective layer on the light reflecting layer by UV irradiation.

First and second molding equipment 12A and 12B
Is a molding machine 20 for injection molding, compression molding, or injection compression molding of a resin material such as polycarbonate to produce a substrate having a tracking groove or an unevenness (groove) representing information such as an address signal formed on one main surface. A cooling unit 22 for cooling the substrate taken out of the molding machine 20, and an accumulating unit 26 (stack pole turntable) on which a plurality of stack poles 24 for stacking and storing the cooled substrates are stored.
Having.

The coating equipment 14 has three processing units 30 and 32
And 34, the first processing section 30 includes a stack pole storage section 40 for storing the stack poles 24 transported from the first and second molding facilities 12A and 12B, and a stack pole storage section 40 for storing the stack poles. A first transport mechanism 42 that takes out the substrates one by one from the stack pole 24 accommodated in the unit 40 and transports the substrates to the next process; And an electrostatic blow mechanism 44 for removing.

The second processing section 32 includes a second transport mechanism 46 for sequentially transporting the substrate, which has been subjected to the electrostatic blow processing in the first processing section 30, to the next step, and transporting the substrate by the second transport mechanism 46. And a third transport mechanism 50 that transports the dye-coated substrates one by one to the next process, one by one. The dye application mechanism 48 includes six spin coaters 52.

The third processing unit 34 cleans the back surface of one substrate transported by the third transport mechanism 50, and transports the substrate after the back surface cleaning to the next step. The fourth transport mechanism 56, a numbering mechanism 58 that performs engraving of a lot number or the like on the substrate transported by the fourth transport mechanism 56 by, for example, an ink jet, and a substrate that has completed the engraving of the lot number or the like. A fifth transport mechanism 60 for transporting the substrate to the process, an inspection mechanism 62 for inspecting the substrate transported by the fifth transport mechanism 60 for a defect and a film thickness of the dye recording layer, and an inspection mechanism 62 Sorting mechanism 68 for sorting the substrate into stack poles 64 for normal products or stack poles 66 for NG according to the inspection results of
And

A first partition plate 70 is provided between the first processing unit 30 and the second processing unit 32, and the second processing unit 32 and the third processing unit 34 have the same second partition plate. A partition plate 72 is provided. An opening (not shown) is formed below the first partition plate 70 to such an extent that the transfer path of the substrate by the second transfer mechanism 46 is not blocked. An opening (not shown) is formed so as not to block the substrate transfer path by the third transfer mechanism 50.

The post-processing facility 16 includes a stack pole storage section 80 for storing stack poles 64 for normal products conveyed from the coating apparatus 14, and a stack pole 64 stored in the stack pole storage section 80. A sixth transport mechanism 82 that takes out substrates one by one and transports them to the next process;
A first electrostatic blow mechanism 84 for removing static electricity from one substrate transported by the sixth transport mechanism 82
And a seventh transport mechanism 86 for sequentially transporting the substrate after the electrostatic blow processing to the next step, and forming a light reflecting layer on one main surface of the substrate transported by the seventh transport mechanism 86 by sputtering. Transport mechanism 90 for sequentially transporting the substrate after the sputtering of the light reflection layer to the next step, and cleaning the periphery (edge portion) of the substrate transported by the eighth transport mechanism 90 Edge cleaning mechanism 9
And 2.

Further, the post-processing equipment 16 includes a second electrostatic blow mechanism 94 for removing static electricity from the substrate after edge cleaning, and a second electrostatic blow mechanism 94 for removing one main surface of the substrate after electrostatic blow processing. UV curable liquid application mechanism 96 for applying UV curable liquid
And a spin mechanism 9 for rotating the substrate on which the UV curing liquid has been applied at a high speed so as to make the applied thickness of the UV curing liquid on the substrate uniform.
8, a UV irradiation mechanism 10 for curing the UV curing liquid by irradiating ultraviolet rays to the substrate after the application of the UV curing liquid and the spin treatment to form a protective layer on one main surface of the substrate
0 and a second electrostatic blow mechanism 94, a UV curing liquid coating mechanism 96, a spin mechanism 98 and a UV irradiation mechanism 10
And a tenth transport mechanism 10 for transporting the substrate irradiated with UV to the next step.
4, a defect inspection mechanism 106 for inspecting the substrate transported by the tenth transport mechanism 104 for defects on the coating surface and the protective layer surface, and a defect inspection mechanism 106 for inspecting signal characteristics due to grooves formed on the substrate. It has a characteristic inspection mechanism 108 and a selection mechanism 114 for selecting a substrate into a stack pole 110 for a normal product or a stack pole 112 for NG according to the inspection results of the defect inspection mechanism 106 and the characteristic inspection mechanism 108. .

Here, the configuration of one spin coater 52 will be described with reference to FIGS.

As shown in FIGS. 2 and 3, the spin coater 52 includes a solution supply device 400, a spinner head device 402, and a scattering prevention wall 404.

As shown in FIG. 4, the solution supply device 400 is filled with a dye solution, and a pressure tank 452 in which the pressure applied to the dye solution is adjusted by a regulator 450. A valve device 408 for controlling discharge and its stop by opening and closing a valve
And a conduit 454 that is routed from the pressurized tank 452 to the valve device 408 and supplies the dye solution filled in the pressurized tank 452 to the valve device 408. The predetermined amount is dropped on the surface of the substrate 202 through 406. The pressure applied to the dye solution in the pressurized tank 452 is set to 1 kgf / cm ² or less.

This solution supply device 400 is shown in FIGS.
As shown in FIG. 5, a handling mechanism 414 having a support plate 410 for supporting the nozzle 406 downward and a motor 412 for horizontally rotating the support plate 410, pivots from the standby position to a position above the substrate 202. It is configured to be able to.

The valve device 408 is, as shown in FIG.
A quick exhaust valve 456 is provided to open and close the internal valve by fluid pressure, and a fluid supply system 458 is provided.
And a speed controller (first and second speed controllers 462 and 464) for adjusting the flow rate of the fluid, respectively, are connected to the exhaust system 460.

The quick exhaust valve 456 is connected to the fluid supply system 4.
An input port 466 to which the valve 58 is connected, an output port 470 to which the valve device main body 468 is connected, and an exhaust port 472 connected to the fluid exhaust system 460.

The fluid introduced from the fluid supply system 458 is supplied into the valve device main body 468 through the input port 466 and the output port 470 of the quick exhaust valve 456, and the fluid in the valve device main body 468 corresponding to the supply of the fluid is supplied. The internal valve operates in the opening direction as the pressure increases. Therefore, the opening speed of the valve (change in the opening degree of the valve per unit time) is proportional to the supply amount of the fluid per unit time, and this supply amount is determined by the opening degree of the first speed controller 462. It is adjustable.

By operating the valve in the opening direction, the dye solution supplied from the pressurized tank 452 is supplied to the valve device 4.
08 and is applied onto the substrate 202. At this time, as shown in FIG.
The discharge amount increases almost proportionally with the elapse of time in response to the increase in the opening degree of the valve, and the discharge amount becomes constant at a stage after a certain period of time, that is, at a stage when the valve is fully opened.

That is, in the transition stage in which the valve is being opened, the coating speed increases almost proportionally, and becomes constant when the valve is fully opened.

The change width (gradient on the characteristic) of the discharge amount in the transition stage in which the discharge amount increases proportionally depends on the opening speed of the valve, and decreases as the opening speed decreases. In other words, the smaller the opening of the first speed controller 462, the smaller the width of change in the ejection amount (gradient in characteristics), and the time when the valve is fully opened from the time t0 when the application of the dye solution is started (the time when the valve is fully opened) The time τs up to t1 when the application speed becomes constant becomes longer. Conversely, the first
The greater the opening of the speed controller 462, the greater the range of change in the discharge amount, and the time τ from the time t0 when the application of the dye solution starts to the time t1 when the valve is fully opened.
s becomes shorter. Here, the time point t0 at which the application of the dye solution is started refers to the time point at which the dye solution starts to emerge from the tip of the nozzle 406.

In the present embodiment, the time τs from the time t0 when the application of the dye solution is started to the time t1 when the valve is fully opened is set to be 0.1 second or more and 1 second or less. In order to satisfy this condition, in this embodiment, by setting the opening of the first speed controller 462 to 5% or more and 50% or less, the opening speed of the valve is set to 5% or more with respect to the maximum speed. 50% or less.

This makes it possible to prevent the dye solution from scattering in all directions at the time when the dye solution falls onto the substrate 202, thereby preventing appearance defects from occurring.

The fluid in the valve device main body 468 is guided to the fluid exhaust system 460 through the output port 470 and the exhaust port 472. The internal valve operates in the closing direction as the pressure decreases. Accordingly, the closing speed of the valve is proportional to the amount of fluid exhausted per unit time, and this exhaust amount can be adjusted by the opening of the second speed controller 464.

When the valve operates in the closing direction, the discharge of the dye solution through the nozzle 406 is stopped, and the dye coating process on one substrate 202 is completed.

At this time, as shown in FIG. 5, in response to the decrease in the opening of the valve, the discharge amount decreases almost proportionally with the passage of time. The discharge amount of the solution is 0, that is, the discharge of the dye solution is stopped.

Also in this case, the width of change (gradient in characteristics) of the discharge amount at the stage where the discharge amount decreases proportionally depends on the closing speed of the valve, and becomes smaller as the closing speed becomes smaller. In other words, the second speed controller 4
The smaller the opening of the aperture 64, the smaller the change width of the discharge amount, and the time from when the application stop of the dye solution is started t2 to when the valve is fully closed (the time when the discharge amount of the dye solution becomes 0) t
The time τe up to 3 becomes longer. Conversely, the greater the degree of opening of the second speed controller 464, the greater the range of change in the discharge amount, and the shorter the time τe from the time t2 when the application of the dye solution is stopped to the time t3 when the valve is fully closed. .

In this embodiment, the time τ from the time t2 at which the application of the dye solution is stopped to the time t3 when the valve is fully closed is set.
The opening of the second speed controller 464 is set to 100% so that e becomes as short as possible.

On the other hand, as shown in FIGS. 2 and 3, the spinner head device 402 is disposed below the solution supply device 400, and the substrate 202 is horizontally held by a detachable fixing member 420. At the same time, the shaft can be rotated by a drive motor (not shown).

The dye solution dropped from the nozzle 406 of the solution supply device 400 onto the substrate 202 rotating while being held horizontally by the spinner head device 402 flows on the surface of the substrate 202 to the outer peripheral side. Postpone. And
The excess dye solution is shaken off at the outer peripheral edge of the substrate 202,
The film is released to the outside and then dried to form a coating film (dye recording layer 204) on the surface of the substrate 202.

The scattering prevention wall 404 is provided in order to prevent the extra dye solution discharged from the outer peripheral edge of the substrate 202 to the outside from scattering to the periphery.
2 are arranged around the spinner head device 402 so as to be formed. Excess dye solution collected through the shatterproof wall 404 is collected through the drain 424.

The local exhaust of each of the spin coaters 52 in the second processing unit 32 (see FIG. 1) uses the air taken in from the opening 422 formed above the scattering prevention wall 404 on the surface of the substrate 202. Exhaust pipe 42 attached below each spinner head device 402.
6 to be exhausted.

As shown in FIGS. 6 and 7, the nozzle 406 of the solution supply device 400 has an elongated cylindrical nozzle body 432 having a through hole 430 formed in the axial direction, and a support plate 410 ( (See FIG. 3). The nozzle body 432 has a front end surface and a surface whose outside or inside, or both wall surfaces within 1 mm or more from the front end surface, are made of a fluorine compound. As the fluorine compound, for example, polytetrafluoroethylene, a substance containing polytetrafluoroethylene, or the like can be used.

As an example of a preferable nozzle 406 used in this embodiment, for example, as shown in FIG. 7, a tip surface of a nozzle body 432 and a range of 1 mm or more from the tip surface are formed using a fluorine compound. Nozzle 406
Alternatively, as shown in FIG.
Nozzles 406 whose outer and / or inner surfaces within a range of 1 mm or more from 0 and the tip surface 440 thereof, or both wall surfaces 442 and 444 are coated with a fluorine compound.

When the tip surface of the nozzle body 432 and the area of 1 mm or more from the tip surface are formed of a fluorine compound,
In consideration of the strength and the like, it is practically preferable that the nozzle body 432 is formed of, for example, stainless steel, and that the front end face and the range of up to 5 mm from the front end face are formed of a fluorine compound.

Also, as shown in FIG.
In the case where the front end surface 440 and the outer or inner side of the end surface 440 from the end surface 440 or more, or both of the wall surfaces 442 and 444 are coated with a fluorine compound, the nozzle body 43
10 mm or more from the tip surface 440 of the second, more preferably,
Preferably, the entire area of the nozzle body 432 is covered with a fluorine compound. The thickness of the coating is not particularly limited, but is suitably in the range of 5 to 500 μm. As described above, stainless steel is preferable as the material of the nozzle body 432. The diameter of the through hole 430 formed in the nozzle main body 432 is generally in the range of 0.5 to 1.0 mm.

Next, a process of manufacturing an optical disk by the manufacturing system 10 will be described with reference to FIGS. 9A to 11.

First, in a molding machine 20 in the first and second molding facilities 12A and 12B, a resin material such as polycarbonate is subjected to injection molding, compression molding or injection compression molding, and as shown in FIG. A groove 2 for representing information such as a tracking groove or an address signal;
The substrate 202 on which the “00” is formed is manufactured.

Examples of the material of the substrate 202 include acrylic resins such as polycarbonate and polymetal methacrylate, vinyl chloride resins such as polyvinyl chloride and vinyl chloride copolymer, epoxy resins, amorphous polyolefin and polyester. They can be used together if desired. Among the above materials, polycarbonate is preferred from the viewpoints of moisture resistance, dimensional stability, cost, and the like. The depth of the groove 200 is 0.0
It is preferably in the range of 1 to 0.3 μm, and its half width is preferably in the range of 0.2 to 0.9 μm.

The substrate 202 taken out of the molding machine 20
After being cooled in the cooling unit 22 in the subsequent stage, the wafer is stacked on the stack pole 24 with one main surface directed downward. At the stage when a predetermined number of substrates 202 are stacked on the stack pole 24, the stack pole 24 is taken out from the molding facilities 12A and 12B, and is conveyed to the next coating facility 14, where the stack pole storage section 40 in the coating facility 14 is placed.
To be housed. This transfer may be performed by a trolley or by a self-propelled automatic transfer device.

At the stage when the stack poles 24 are accommodated in the stack pole accommodating section 40, the first transport mechanism 42 operates, and the substrates 202 are taken out one by one from the stack poles 24 and transferred to the subsequent electrostatic blow mechanism 44. Transport. After the static electricity is removed by the electrostatic blow mechanism 44, the substrate 202 transported to the electrostatic blow mechanism 44 is transported to the next dye coating mechanism 48 via the second transport mechanism 46, and is subjected to six spin coatings. One of the devices 52 is supplied to one of the spin coaters 52. After the dye solution is applied to one main surface of the substrate 202 loaded into the spin coater 52, the substrate 202 is rotated at a high speed to make the thickness of the dye solution uniform, and then subjected to a drying process. This results in FIG. 9B
As shown in FIG. 2, the dye recording layer 20 is formed on one main surface of the substrate 202.
4 will be formed.

That is, the substrate 202 loaded into the spin coater 52 is mounted on the spinner head device 402 shown in FIG. Next, a predetermined amount of the dye solution supplied from the pressurized tank is adjusted by the valve device 408, and is dropped through the nozzle 406 on the inner peripheral side on the substrate 202.

As described above, the nozzle 406 has a front end face and an outer or inner side within a range of 1 mm or more from the front end face, or both of the walls have a surface made of a fluorine compound. Adhesion does not easily occur, and it is hard to dry to cause precipitation of the dye and its deposit. Therefore, the coating film can be formed smoothly without obstruction such as coating film defects.

As the dye solution, a dye solution obtained by dissolving a dye in an appropriate solvent is used. The concentration of the dye in the dye solution is generally in the range from 0.01 to 15% by weight, preferably in the range from 0.1 to 10% by weight, particularly preferably from 0.1 to 10% by weight.
5-5% by weight, most preferably 0.5-3% by weight
In the range.

The spinner head device 4 is driven by a drive motor.
02 is capable of high-speed rotation. The dye solution dropped onto the substrate 202 flows in the outer peripheral direction on the surface of the substrate 202 by rotation of the spinner head device 402, and reaches the outer peripheral edge of the substrate 202 while forming a coating film.

In particular, in the present embodiment, a dye solution is applied onto the substrate 202 in a processing procedure as shown in FIG. First, in step S1 in FIG. 11, the substrate 202 is raised to a rotation speed of about 270 rpm, and at the same time, the support plate 410 (see FIG. 3) in the solution supply device 400 is rotated in the horizontal direction to cause the nozzle 406 to rotate, Bring to a position with a radius of 46 mm.

Thereafter, in step S2, the substrate 20
The application of the dye solution is started while keeping the rotation speed of 270 rpm at 270 rpm, and in this state, the support plate 410 is rotated in the horizontal direction to move the nozzle 406 to a predetermined position Ps on the substrate 202 (see FIGS. 4 and 12). To move in about 2 seconds.

Here, the predetermined position Ps is, as shown in FIGS. 4 and 12, 5 m from the outer peripheral edge P1 of the substrate 202.
m or more on the inner circumference side of the substrate 202, that is, the uncoated portion on the substrate 202, that is, the dye recording layer 204.
5 m from the inner end P0 of the region to be formed as
m or more, preferably 10 mm or more, more preferably 15 mm or more.
mm or more near the outer periphery. In the present embodiment, the position is 23 mm in radius.

Next, in step S3, the application of the dye solution is started, and after moving once to the inner peripheral side, while applying the dye solution, the support plate 410 is rotated in the horizontal direction so that the nozzle 406 has a radius of 40 mm. Is taken over about 3 seconds, and at the same time, the rotation speed of the substrate 202 is increased to 550 rpm.

Thereafter, in step S4, the application of the dye solution is stopped, and the support plate 410 is rotated in the horizontal direction to return the nozzle 406 to its original position (initial state).

Next, in step S5, the substrate 202
Is increased to 630 rpm over 6 seconds.

Thereafter, in step S6, the substrate 20
2 is increased to 1400 rpm over 6.3 seconds.

Then, in step S7, the substrate 20
2 is increased to 2200 rpm over 1.7 seconds, and then the rotation speed of the substrate 202 (= 2200 rpm)
For 5 seconds.

The excess dye solution that has reached the outer peripheral edge of the substrate 202 due to the increase in the number of rotations in steps S5 to S7 is further shaken off by the centrifugal force and scattered around the edge of the substrate 202. The extra dye solution that has scattered collides with the anti-scattering wall 404 as shown in FIGS.
After being collected in a saucer provided below, it is collected through the drain 424. Drying of the coating film is performed during the formation process and after the formation of the coating film. The thickness of the coating film (dye recording layer) is generally in the range of 20 to 500 nm, preferably 5 to 500 nm.
It is provided in the range of 0 to 300 nm.

The above steps S1 to S7
In the dye coating process in the above, the air velocity of the clean air sent into the coating equipment 14 is set to about 0.4 m / sec or less by an air conditioning system (not shown). That is,
Air-conditioning air velocity on the dye-coated surface of the substrate 202 is about 0.4 m
/ Sec or less.

When the processing in step S7 is completed, the rotation of the substrate 202 is stopped, and the coating process of the dye solution on the substrate 202 is completed.

Here, the dye used in the dye recording layer 204 is not particularly limited. Examples of dyes that can be used include:
Cyanine dye, phthalocyanine dye, imidazoquinoxaline dye, pyrylium / thiopyrylium dye, azulenium dye, squalilium dye, N
i, Cr and other metal complex dyes, naphthoquinone dyes,
Examples include anthraquinone dyes, indophenol dyes, indoaniline dyes, triphenylmethane dyes, merocyanine dyes, oxonol dyes, aminium / diimmonium dyes, and nitroso compounds. Among these dyes, cyanine dyes, phthalocyanine dyes, azulhenium dyes, squalilium dyes, oxonol dyes, and imidazoquinoxaline dyes are preferred.

Examples of the solvent for the coating agent for forming the dye recording layer 204 include esters such as butyl acetate and cellosolve acetate; ketones such as methyl ethyl ketone, cyclohexanone and methyl isobutyl ketone; dichloromethane, 1,2-dichloroethane, and chloroform. Chlorinated hydrocarbons such as amides; amides such as dimethylformamide;
Hydrocarbons such as cyclohexane; tetrahydrofuran,
Ethers such as ethyl ether and dioxane; alcohols such as ethanol, n-propanol, isopropanol, n-butanol and diacetone alcohol;
Fluorinated solvents such as 2,3,3-tetrafluoro-1-propanol; ethylene glycol monomethyl ether;
Examples thereof include glycol ethers such as ethylene glycol monoethyl ether and propylene glycol monomethyl ether.

The above solvents can be used alone or in combination of two or more in consideration of the solubility of the dye used. Preferably, it is a fluorinated solvent such as 2,2,3,3-tetrafluoro-1-propanol. In the dye solution, if necessary, an anti-fading agent or a binder may be added, or various additives such as an antioxidant, a UV absorber, a plasticizer, and a lubricant may be added according to the purpose. It may be added.

Representative examples of the anti-fading agent include nitroso compounds, metal complexes, diimmonium salts and aminium salts. These examples are described in, for example, JP-A-2-300288, JP-A-3-224793, and JP-A-4-224793.
No. 146189.

Examples of the binder include natural organic high molecular substances such as gelatin, cellulose derivatives, dextran, rosin and rubber; and hydrocarbon resins such as polyethylene, polypropylene, polystyrene and polyisobutylene, polyvinyl chloride and polyvinyl chloride. Vinylidene, polyvinyl chloride
Vinyl resins such as polyvinyl acetate copolymer, acrylic resins such as polymethyl acrylate and polymethyl methacrylate, polyvinyl alcohol, chlorinated polyethylene, epoxy resin, butyral resin, rubber derivatives, phenol
Synthetic organic polymers such as precondensates of thermosetting resins such as formaldehyde resins can be mentioned.

When a binder is used, the amount of the binder used is generally 20 parts by weight or less, preferably 10 parts by weight or less, more preferably 5 parts by weight, based on 100 parts by weight of the dye.
Not more than parts by weight.

An undercoat layer is provided on the surface of the substrate 202 on the side where the dye recording layer 204 is provided, for the purpose of improving flatness, improving adhesive strength, and preventing the dye recording layer 204 from being deteriorated. Is also good.

Examples of the material for the undercoat layer include polymethyl methacrylate, acrylic acid / methacrylic acid copolymer,
Styrene / maleic anhydride copolymer, polyvinyl alcohol, N-methylol acrylamide, styrene / vinyl toluene copolymer, chlorosulfonated polyethylene,
Nitrocellulose, polyvinyl chloride, chlorinated polyolefin, polyester, polyimide, vinyl acetate-vinyl chloride copolymer, ethylene-vinyl acetate copolymer, polyethylene, polypropylene, polycarbonate and other high-molecular substances, and silane coupling agents Surface modifiers can be mentioned.

The undercoat layer is prepared by dissolving or dispersing the above substance in an appropriate solvent to prepare a dye solution, and then applying the dye solution to the surface of the substrate by using a coating method such as spin coating, dip coating or extrusion coating. Can be formed. The thickness of the undercoat layer is generally 0.0
In the range of 05 to 20 μm, preferably 0.01 to 10 μm
Is provided in the range.

The substrate 202 on which the dye recording layer 204 is formed
Is transferred to the next back surface cleaning mechanism 54 via the third transport mechanism 50.
And the other side of the main surface of the substrate 202 (back side)
Is washed. Thereafter, the substrate 202 is transported to the next numbering mechanism 58 via the fourth transport mechanism 56,
As shown in the figure, an inscribed mark 47 such as a lot number
6 is performed by ink jet.

Thereafter, the substrate 202 is moved to the fifth transport mechanism 6
Then, the substrate 202 is transported to the next inspection mechanism 62 through which the presence or absence of a defect in the substrate 202 and the thickness of the dye recording layer 204 are inspected. This inspection is performed by irradiating light from the back surface of the substrate 202 and performing image processing on the transmission state of the light using, for example, a CCD camera. The inspection result of the inspection mechanism 62 is sent to the next sorting mechanism 68.

The substrate 202 that has been subjected to the above inspection processing is transported and sorted by the sorting mechanism 68 into a stack pole 64 for normal products or a stack pole 66 for NG based on the inspection result.

At the stage when a predetermined number of substrates 202 are stacked on the stack pole 64 for normal products, the stack pole 64 for normal products is taken out of the coating equipment 14 and transported to the next post-processing equipment 16. It is housed in the stack pole housing section 80 of the post-processing facility 16. This transfer may be performed by a trolley or by a self-propelled automatic transfer device.

At the stage when the stack poles 64 for normal products are accommodated in the stack pole accommodating section 80, the sixth transport mechanism 82 operates, and the substrates 2 are stacked one by one from the stack poles 64.
02 is taken out and transported to the first electrostatic blow mechanism 84 at the subsequent stage. After the static electricity is removed by the first electrostatic blow mechanism 84, the substrate 202 transported to the first electrostatic blow mechanism 84 is transported to the next sputtering mechanism 88 via the seventh transport mechanism 86. You.

The substrate 202 put in the sputtering mechanism 88
As shown in FIG. 9C, a light reflection layer 208 is formed on one entire surface of the main surface except for a peripheral portion (edge portion) 206 by sputtering.

The light-reflective substance, which is the material of the light-reflective layer 208, is a substance having a high reflectivity to laser light, and examples thereof include Mg, Se, Y, Ti, Zr, Hf, V, and N.
b, Ta, Cr, Mo, W, Mn, Re, Fe, Co,
Ni, Ru, Rh, Pd, Ir, Pt, Cu, Ag, A
u, Zn, Cd, Al, Ga, In, Si, Ge, T
e, Pb, Po, Sn, Bi, and other metals and semi-metals or stainless steel.

Of these, preferred are Cr, N
i, Pt, Cu, Ag, Au, Al and stainless steel. These substances may be used alone or in combination of two or more. Alternatively, it may be used as an alloy. Particularly preferred is Ag or an alloy thereof.

The light reflecting layer 208 can be formed on the recording layer by, for example, vapor deposition, sputtering or ion plating of the light reflecting substance.
The thickness of the reflective layer is generally in the range of 10 to 800 nm,
Preferably in the range of 20 to 500 nm, more preferably 5
It is provided in the range of 0 to 300 nm.

The substrate 202 on which the light reflection layer 208 is formed
Is transferred to the next edge cleaning mechanism 9 via the eighth transport mechanism 90.
Then, as shown in FIG. 10A, the edge portion 206 in one main surface of the substrate 202 is cleaned, and the dye recording layer 204 formed on the edge portion 206 is removed. Thereafter, the substrate 202 is transported to the next second electrostatic blow mechanism 94 via the ninth transport mechanism 102, and the static electricity is removed.

Thereafter, the substrate 202 is also conveyed to the UV curable liquid applying mechanism 96 via the ninth transfer mechanism 102, and the UV curable liquid is dropped on a part of one main surface of the substrate 202. Thereafter, the substrate 202 is also transported to the next spin mechanism 98 via the ninth transport mechanism 102 and rotated at a high speed, so that the applied thickness of the UV curing liquid dropped on the substrate 202 is reduced over the entire surface of the substrate. Is made uniform.

In this embodiment, time management is performed so that the time from the formation of the light reflection layer 208 to the application of the UV curing liquid is 2 seconds or more and 5 minutes or less.

Thereafter, the substrate 202 is transported to the next UV irradiation mechanism 100 via the ninth transport mechanism 102, and the UV curing liquid on the substrate 202 is irradiated with ultraviolet rays. As a result, as shown in FIG.
02 so as to cover the dye recording layer 204 and the light reflecting layer 208 formed on one main surface of the protective layer 210 made of a UV curable resin.
Is formed to constitute the optical disc D.

The protection layer 210 is provided on the light reflection layer 208 for the purpose of physically and chemically protecting the dye recording layer 204 and the like. The protective layer 210 can also be provided on the side of the substrate 202 on which the dye recording layer 204 is not provided for the purpose of improving scratch resistance and moisture resistance. As a material used for the protective layer 210, for example, SiO, SiO ₂ , MgF
₂ , inorganic substances such as SnO ₂ and Si ₃ N ₄ and organic substances such as a thermoplastic resin, a thermosetting resin, and a UV-curable resin.

The protective layer 210 can be formed, for example, by laminating a film obtained by extrusion of a plastic on the light reflecting layer 208 and / or the substrate 202 via an adhesive. Alternatively, it may be provided by a method such as vacuum deposition, sputtering, or coating.
In the case of a thermoplastic resin or a thermosetting resin, they can be formed by dissolving these in an appropriate solvent to prepare a dye solution, and then applying and drying the dye solution.

In the case of a UV-curable resin, as described above, a dye solution is prepared as it is or dissolved in an appropriate solvent, and then the dye solution is applied and cured by irradiation with UV light. Can be formed. These dye solutions further contain an antistatic agent, an antioxidant,
Various additives such as a V absorbent may be added according to the purpose. The thickness of the protective layer 210 is generally 0.1 to 100 μm.
Is provided in the range.

Thereafter, the optical disk D is transported to the next defect inspection mechanism 106 and characteristic inspection mechanism 108 via the tenth transport mechanism 104, where the surface of the dye recording layer 204 and the protective layer 2
10, the presence or absence of a defect on the surface of the optical disc D
The signal characteristics of the groove 200 formed in the second groove 2 are inspected. These inspections are performed by irradiating light to both sides of the optical disc D and subjecting the reflected light to image processing by, for example, a CCD camera. The inspection results of the defect inspection mechanism 106 and the characteristic inspection mechanism 108 are sent to the next selection mechanism 114.

The optical disc D that has been subjected to the above-described defect inspection processing and characteristic inspection processing is subjected to a sorting mechanism 1 based on each inspection result.
Depending on 14, stack pole 110 for normal product or NG
Is sorted by the stack pole 112 for use.

When a predetermined number of optical discs D are loaded on the stack pole 110 for normal products, the stack pole 110 is taken out of the post-processing equipment 16 and put into a label printing step (not shown).

As described above, in the manufacturing system 10 according to the present embodiment, when the dye solution for forming the dye recording layer 204 is coated on the substrate 202 while rotating the substrate 202, the coating of the dye solution is performed. A valve device 4 for discharging the dye solution by setting the time τs from the start time t0 to the time t1 when the valve is fully opened to 0.1 second or more and 1 second or less.
08, the opening speed of the valve is reduced, so that the dye solution does not suddenly discharge from the nozzle 406 at the coating start time t0.
02 can be prevented from scattering in four directions when the dye solution falls. As a result, appearance defects can be prevented from occurring, and the yield of the optical disc D can be improved.

In particular, in the present embodiment, the dye solution coating start position Ps should be formed as a dye recording layer 204 at a position separated from the inner uncoated portion P0 by 5 mm or more on the substrate 202, that is, the dye recording layer 204. The position is 5 mm or more from the inner peripheral end P0 of the region toward the outer peripheral side.

If the application start position Ps is sufficiently far from the non-application portion P0 on the inner peripheral side on the substrate 202,
It does not matter if the dye solution scatters. This is because the scattered droplets flow away in the subsequent coating process.

Immediately after the start of coating, the discharge amount of the dye solution changes transiently with the lapse of time and becomes unstable. Therefore, it is preferable to start coating at a position slightly away from the innermost circumference. This is because, when the coating is started from the innermost circumference, uneven coating may be caused, and the inner circumference end of the dye recording layer 204 may not be formed into a clean circle.

In the present embodiment, since the nozzle 406 is once moved to the inner peripheral side from the point of time t0 when the application of the dye solution is started, the inner peripheral end of the dye recording layer 204 has a clean circular shape.

If the coating is started outside of the substrate 202, the dye solution scatters in various directions when hitting the outer peripheral end P1 of the substrate 202, and stains the vicinity of the coated portion, Problems such as adhesion of the solution to the back surface of the substrate 202 occur.

Therefore, the coating start position Ps is preferably on the substrate 202 as in the present embodiment, and more preferably is closer to the inner periphery by 5 mm or more from the outer peripheral end P1 of the substrate 202. In addition, the outer peripheral portion is preferably at least 5 mm, preferably at least 10 mm, more preferably at least 15 mm from the non-coated portion P0 on the inner peripheral side on the substrate 202.

On the other hand, the pressure applied to the dye solution, that is, the pressure in the pressurized tank 452 is 1 kgf / c in the present embodiment.
m ² or less. In general, when the dye solution is applied to the substrate 202, when the discharge of the dye solution is suddenly started, the dye solution scatters in all directions, but when the pressure applied to the dye solution is small, the dye solution does not scatter greatly. No problems such as poor appearance occur.

However, if the pressure is too low, the discharge amount per unit time decreases, and the coating speed becomes slow. Therefore, it takes time to apply a predetermined amount of the dye solution, and as a result, the throughput is reduced. However, production efficiency may be reduced.

Accordingly, the preferable range of the pressure applied to the dye solution is, as described above, the upper limit of 1 kgf / c.
m ² or less, preferably 0.8 kgf / cm ² or less, and most preferably 0.6 kgf / cm ² or less. The lower limit is 0.02 kgf / cm ² or more, preferably 0.1 kgf / cm ² or more.
05 kgf / cm ² or more, most preferably 0.1 kgf
/ Cm ² or more.

[0117]

Next, one experimental example will be described. In this experimental example, when the optical disk D is manufactured by the manufacturing system 10 shown in FIG. 1, the opening degree of the first speed controller 462 was changed for the samples (Examples 1 to 4 and Comparative Examples 1 to 3). It shows the scattering probability at that time, the time until the coating speed is stabilized, and the coating rate.

Here, the scattering probability is calculated based on the distribution of the droplets attached to the inner transparent portion 474 (the portion where the droplets are not desired to be attached) on the substrate 202 in FIG. Is 0% when no is adhered.

The time required for the coating speed to stabilize is as follows:
As shown in FIG. 5, this refers to a time τs from a time point t0 at which the application of the dye solution is started to a time point t1 at which the application speed of the dye solution becomes constant (the time when the valve is fully opened). The coating rate is determined based on the substrate 20
The state of application of the dye solution to No. 2 was determined by a film thickness inspection of the dye recording layer 204.
%.

The formation of the dye recording layer 204 is as follows. A combination of 2.65 g of a cyanine dye compound represented by the following general formula (1) and 0.265 g of a fading inhibitor represented by the following general formula (2) is blended, and these are blended with the following general formula (3) 2,2,3,3-tetrafluoro- represented by
It was dissolved in 100 cc of 1-propanol to prepare a dye solution for forming a recording layer.

[0121]

Embedded image

[0122]

Embedded image

[0123]

Embedded image

Thereafter, a spiral groove (track pitch: 1.6 μm, groove width: 0.4 μm) is formed on the surface.
m, groove depth: 0.16 μm) formed by injection molding a polycarbonate substrate (diameter: 120 mm,
The dye solution is applied to the surface of the groove side having a thickness of 1.2 mm) by spin coating while changing the rotation speed from 270 rpm to 2000 rpm, and the dye recording layer 2 is formed.
04 (thickness in the groove: about 200 nm).
The coating treatment of the dye solution was performed according to the steps shown in FIG. Further, the pressure of the pressurized tank is set to 0.3 kgf / cm ²
And

FIG. 13 shows the results of this experiment. From this experimental result, it can be seen that in Examples 1 to 4 and Comparative Example 1 in which the time τs until stabilization was longer than 0.1 second, the scattering probability was 0% and there was no defective appearance.

However, in Comparative Example 1, since the opening of the first speed controller 462 was set to 2%, which is lower than 5%, a portion not applied was generated due to insufficient discharge of the dye solution, and the coating rate was 20%. %Met.

Therefore, from the results of this experiment, the opening degree of the first speed controller 462 is preferably in the range of 5% or more and 50% or less, more preferably 20% or more and 5% or less.
It turns out that it is 0% or less.

The method of manufacturing an optical information recording medium according to the present invention is not limited to the above-described embodiment, but may adopt various configurations without departing from the spirit of the present invention.

[0129]

As described above, according to the method for manufacturing an optical information recording medium according to the present invention, it is possible to prevent the scattering of the dye solution, to prevent appearance defects and to reduce the yield of the optical information recording medium. Improvement can be achieved.

[Brief description of the drawings]

FIG. 1 is a configuration diagram illustrating an example of a manufacturing system according to an embodiment.

FIG. 2 is a configuration diagram showing a spin coater installed in a coating facility.

FIG. 3 is a perspective view showing a spin coater installed in a coating facility.

FIG. 4 is a configuration diagram showing a solution supply device constituting the spin coating device.

FIG. 5 is a characteristic diagram showing a change with time of an amount (discharge amount) of a dye solution discharged from a valve device.

FIG. 6 is a plan view showing a nozzle of the valve device.

FIG. 7 is a side view showing an example of a nozzle of the valve device.

FIG. 8 is an enlarged cross-sectional view showing another example of the nozzle of the valve device with a part thereof omitted.

9A is a process diagram showing a state in which a groove is formed on a substrate, FIG. 9B is a process diagram showing a state in which a dye recording layer is formed on the substrate, and FIG. 9C is light reflection on the substrate. FIG. 4 is a process diagram showing a state in which a layer is formed.

FIG. 10A is a process diagram showing a state where an edge portion of the substrate is cleaned, and FIG. 10B is a process diagram showing a state where a protective layer is formed on the substrate.

FIG. 11 illustrates a manufacturing system according to the present embodiment.
FIG. 4 is a process block diagram illustrating a processing procedure when a dye solution is applied to a substrate.

FIG. 12 is a diagram for explaining a coating start position on a substrate.

FIG. 13 is a table showing the results of an experimental example.

FIG. 14 is an explanatory diagram showing scattering of a dye solution generated when a dye solution is applied.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Manufacturing system 14 ... Coating equipment 48 ... Dye coating mechanism 52 ... Spin coating device 202 ... Substrate 204 ... Dye recording layer 400 ... Solution supply device 406 ... Nozzle 408 ... Valve device 452 ... Pressurized tank 456 ... Rapid exhaust valve 458 ... Fluid supply system 460 Fluid exhaust system 462 First speed controller 464 Second speed controller 466 Input port 468 Valve body 470 Output port 472 Exhaust port 474 Transparent part 476 Engraved D optical disk

Claims (7)

[Claims] 1. A method for manufacturing a heat mode optical information recording medium having a recording layer on which information can be recorded by irradiating a laser beam on a substrate, wherein the recording layer is formed while rotating the substrate. Wherein the time from the start of application of the solution to the time when the application speed of the solution becomes constant is 0.1 seconds or more and 1 second or less when the solution is applied to the substrate. Manufacturing method of recording medium. 2. The method for manufacturing an optical information recording medium according to claim 1, wherein a valve device for executing and stopping the discharge of the solution to the substrate by opening and closing a valve is used, and the opening speed of the valve is set to a maximum speed. 5% or more for
A method for producing an optical information recording medium, wherein the content is set to 0% or less. 3. The method for manufacturing an optical information recording medium according to claim 2, wherein when the valve is opened and closed by a fluid pressure, a speed controller for controlling a flow rate of a fluid supplied to the valve device is provided. A method for manufacturing an optical information recording medium, wherein an opening of the speed controller for determining a flow rate of the fluid is set to 5% or more and 50% or less. 4. The method for producing an optical information recording medium according to claim 1, wherein said solution is a dye-containing organic solvent. 5. The method for manufacturing an optical information recording medium according to claim 1, wherein a position at which coating is started is on the substrate. Method. 6. A method for manufacturing an optical information recording medium according to claim 5, wherein the position at which the coating is started is separated from the uncoated portion on the inner peripheral side of the substrate by 5 mm or more. Manufacturing method of recording medium. 7. The method for manufacturing an optical information recording medium according to claim 1, wherein the pressure applied to the solution is 1 kgf / cm ² or less. Production method.